Shearer, the Premier League’s all-time leading goalscorer, told Match of the Day 2 on the back of a 2-1 defeat for United which saw more questions asked of their big-money frontman: “No one was asking these questions earlier on in the season when Lukaku was scoring 11 goals in his first 10 games.

“No one was asking the question of Mourinho then and whether he had improved Lukaku.

“He's not doing enough in games and, I hate saying it, to justify his fee.

“He looks to be lacking in confidence, two in 14 now, but in his defence with some of the balls and some of the service he was feeding on scraps.

“Everything seems a second or two too slow and by the time he's made his mind up, it's gone.”

Things could not have gone much worse for him against City in his latest outing, as he contributed significantly to Pep Guardiola’s team claiming derby spoils.

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The ball bounced off him into the path of David Silva for the opening goal after he failed to deal with a delivery into the box, while it was his wayward clearance which ricocheted kindly into the path of Nicolas Otamendi for the winner.

Lukaku was also denied the opportunity to snatch would could have been a precious point for United when he turned a close-range effort into the face of City goalkeeper Ederson, rather than placing a shot either side of the Brazilian.

His next opportunity to get back on track could come against Bournemouth on Wednesday, with Mourinho having previously spoken of his unwavering belief in his leading marksman.